Utomatic sizing device for measuring apparatus

ABSTRACT

The automatic sizing device of the present invention provides two amplifiers for low sensitivity range and for high sensitivity range and these amplifiers are used in the following manner. That is, the amplifier for the low sensitivity range is used in normal grinding for detecting a grinding limit for which the grinding speed and the amount of grinding are measured and the whole range of procedure of the grinding to an on size can be observed. During the above-mentioned normal grinding, the grinding speed is changed to the speed for precise grinding. And when the amplifier for high sensitivity range is used in a finishing grinding, a high accuracy for grinding can be obtained, and the signals for a spark out and for an on size can be precisely generated.

United States Patent [191 Kubo Dec. 4, 1973 [54] AUTOMATIC SIZING DEVICE FOR 2,102,517 12/1937 Crmpton.... 51 /165.91

MEASURING APPARATUS [75 1 Inventor: Kakuzo Kubo, Tokyo, Japan Primary Examiner-Harold D. Whitehead Attorney-Allan Ratner et a1.

[73] Assignee: Tokyo Seimitsu Co., Ltd., Tokyo,

Japan [57] ABSTRACT [22] Filed: June 17, 1971 The automatic S1Z1l1g device of the present Invention [21] PP N 154,078 provides two amplifiers for low sensitivity range and for high sensitivity range and these amplifiers are used Foreign Application Priority Data in the following manner. That is, the amplifier for the June 19, 1970 Japan /60284 (utility model) low sensitivity range is used in normal grinding for detecting a grinding limit for which the grinding speed and the amount of grinding are measured and the [52] US. Cl. ..51/165.77, 51/l65.9l [51] int Cl B24) 49/04 whole range of procedure of the grinding to an on size [58] Fie'ld 83 6 88 can be observed. During the above-mentioned normal 1 2, grinding, the grinding speed is changed to the speed for precise grinding. And when the amplifier for high References Cited sensitivity range is used in a finishing grinding, a high accuracy for grinding can be obtained, and the signals UNITED STATES PATENTS for a spark out and for an on size can be precise] en- 2521979 '9/1950 J 51/165 91 d yg agen crate 3,578,871 5/1971 Sakanotu... 318/563 X 3,138,750 6/1964 Borger 318/474 X 4 Claims, 4 Drawing Figures i=1 WT SY N c -O AMP RECTIFIER E:

AME CIRCUIT j 1 g ,8 3 L EXCITING 5 6 J cmcuw E: 8 l IO ISYT J TRlG. CIRCUIT L H @g 2ND 2ND 1-o/l4 0c TRIG, AMP ClRCUlT I 2ND V ii TRIG. CIRCUIT {I (I END 9 l-fi TRIG,

CIRCUIT PATENTED 41973 SHEEI 2 0F 4 ited.

AUTOMATIC SIZING DEVICE FOR MEASURING APPARATUS The present invention relates toan automatic sizing device of an automatic measuring apparatus, mainly utilized in an automaticgrindingdevice.

I An automatic measuring apparatusis one of a measuring control apparatus which directly measures a dimension of a work undergrinding, applies the signal corresponding to a variation of the dimension of the work to the grinding device thereby controlling the grinding speed and the amount of the ,grinding aHd stops the grinding motion whenthe dimension of the work reaches to an on size. 7

Generally used automatic measuring devices relate to the utilization of the analogue measuringtechnique. However, an accuracy limit in the analoguemeasurement does not generallyexceed about 1-1 0.5. percent of the full scale of the indicator: used in the measuring device. Accordingly when the full range of the indicator is utilized for observing the whole range of .the procedure of the grinding to an on size, it is natural that the accuracy for a finishing grinding deteriorates.

The object of the present invention is to overcome the above-mentioned drawback.

Another object of the present invention is to provide an automatic sizing device which can observe the whole range of process ofgthe grinding andsimultaneously carries out a finishing grinding with a high accuracy. i

Further object of the present invention is to provide an automatic sizing device which contains one amplifier for anormal grinding and another amplifier fora finishing grinding. I

Further features and advantage of the present invention will be apparent from the ensuing description with reference to the accompanying drawings to which, however, the scope of the invention is in no way lim- FIG. 1 shows a block diagram of one embodiment of a conventional sizing device of an automatic measuring apparatus,

FIG. 2 shows a block diagram of one embodiment of a sizing device of the present invention,

FIG. 3 showsa diagram explaining the relation between the variation of thedimension of the workand the reading of the indicator, and

FIG. 4 shows a circuit diagram of one embodiment of FIG. 2.

Referring to FIG. 1, an operation of a conventional automatic sizing device is carried outin the following manner. A grinder l of a grinding device contacts a work 2 grinding same. A variation of the dimension of the work 2 ground by the grinder'l is converted to an electric output signal of a measuring unit part 3. The output signal of themeasuring unit part 3 is supplied via an amplifier 4 to a synchronous rectifier 5. An exciting oscillator is provided for exciting a detector in the measuring unit part 3 and the synchronous rectifier 5. The output of the synchronous rectifier 5 is supplied via trigger circuits 8 and 9 to relay driving circuits [3 and 14, and the control actions, that is, a high speed grinding, a finishing grinding, a grinding stop, a rear back of a grinder etc. are all carried out by the output of the relay driving circuit. In this case, the whole range of process of the grinding is observed by an indicator l1, and the trigger circuits 8 and 9 are operated by the output of the synchronous rectifierS all over the whole range of procedure of .thetgiinding. As a result,.the accuracy for a finishinggrindingdeteriorates.

Referring to FIG. 2, the device according tothepresent'invention has the samefunction as faras the synchronous rectifier 5. However, in the present invention,

the outputof the synchronous rectifier 5 is amplified. by

amplifiers 6 and .7 are supplied to an indicator ,llvia input terminal L' andI-I of the .commutating switch 12 respectively. The output of the first trigger circuits 8, 8, are provided for a wide range control signahfor example,.the normal grinding,.the high speed grinding, etc. On the other hand,- the output. of the second trigger circuits 9, 9', are. provided for a narrow range control signal for precise grinding, for example, a finishing grinding, a grinding stop, a rear back of .a grinder, etc. The control signals for: the grinding device are generated at a predetermined .value on the L range of the indicator 11 by setting a I trigger level in the abovementioned trigger circuits. The numbers of these control signals and these trigger circuits are different according to the number and the level of the control signal. According to. the level, the relay driving circuit is connected to the first DOamplifier 6 or thesecond DC amplifier7, and if necessary, directly to thesynchronous rectifier 5 or to a third DC amplifier specially provided.

cates the variation of the dimension of thework, the ordinate shows the reading of the indicator 11, anda dotted line FS shows the full scale of the indicator 11. The straight line B shows the low sensitivity range obtained via input terminal Lwhich corresponds to the input of the first trigger circuits 8, 8, and the straight line A shows the high sensitivity range obtained via input terminal H which corresponds to the input of thesec- 0nd trigger circuits-9, 9', It isseen that the straight line B shows the whole range of. a variation of the dimension of the work 2 and the straightline A shows the narrow range near the on size of the work 2, that is, the straight line A is. an enlargement of the straightline 3 near the on size. Of course, the cross point of the straight linesA and B is an on size position. Further, as

mentionedaboveflhe control signals are generated on the appropriate points on the straightlines by setting a trigger level of the trigger circuit. Also, it is seen that the switch 12 indicates only the actual value, and the accuracy of the on size of the work is determined by the output of the trigger circuits 9, 9", thereby ensuring a' high degree of accuracy.

FIG..4 shows the circuit block diagramof the automatic circuit. device of the present invention. Thefollowing explanation is given for the case where two trigger circuits and two control signals are provided in the device. Referring to FIG. 4, the measuring part 3 .is composed of a differential transformer T the primary winding thereof is excited by the exciting oscillator 10. A feeler F displaces in accordance with a variation of I the dimension of the work, and the output of the measuring unit part 3 .varies with the position of the feeler F. A mean output level of the measuring part 3 is fixed at a proper measuring level by the potentiometer RV,,

and is applied via the amplifier 4 to a primary winding of the transformer T of the synchronous rectifier 5. In addition, another output of the exciting oscillator is applied via a transformer T between a neutral top on the secondary winding of the transformer T and ground. DC output of the synchronous rectifier circuit 5 is applied to the first DC amplifier and this output of the first DC amplifier is always indicated by the low sensitivity range of the indicator 11. An output of the first DC amplifier is also applied to the first trigger circuit 8, and to the second DC amplifier 7. The output of the second DC amplifier is indicated, if necessary, by the high sensitivity range of the indicator l1 and is also applied to the second trigger circuit 9.

The trigger circuit 8 and 9 have essentially the same function, therefore it is sufficient to explain only the trigger circuit 8. The trigger circuit 8 is basically a schumit trigger circuit, and consists of an operational amplifier A composed of an integrated circuit, a positive feedback means comprising R R and R a level setting means composed of a positive potential level +B a negative potential level, and a potentiometer RV The variable point of the potentiometer RV is set in the position where a predetermined control signal for the normal grinding is generated. When the output level of the first DC amplifier exceeds the abovementioned set level, the above-mentioned trigger circuit changes its binary level state. This changed level is amplified by a transistor TR and causes a current to flow in the coil of the relay R. The relay contacts R-a,

I R-b and R-c are operated by the current flow in the coil and form the control output signals.

In the operation of the above-mentioned circuit, firstly a master is placed in the position of the work 2, and determines the condition of the high speed cutting, the finishing grinding, a spark out, the rear back of the grinder, etc. Working condition of the work 2 is detected by the measuring unit part 3, and a speed change of the high speed cutting and the finishing grinding etc. are controlled by the output of the trigger circuit 8, and the spark out and the rear back of the grinder etc. are controlled by the output of the trigger circuit 9.

' What is claimed is:

1., An automatic sizing device for measuring apparatus comprising, means for detecting a variation of a dimension of a work, converting means for converting said variation into an electric quantity, an output of said converting means being applied via a synchronous rectifier to first amplifier means, an output of said first amplifier means being indicated on an indicator as a variation of a whole range of process of a grinding, an output of said first amplifier means being applied to a single or multiple first trigger circuits, outputs of said first trigger circuits generating a single or multiple control signals for controlling a working condition of said work, said output of said first amplifier means being applied via second amplifier means to a single or multiple second trigger circuits, outputs of said second triggers circuit generating a single or multiple control signals for controlling a working condition near and/or on size.

2. The automatic sizing device for measuring apparatus according to claim 1, wherein said first and second trigger circuits each include, respectively, an operational amplifier with a positive feed back and a potentiometer for setting a trigger level of said operational amplifier, an output of said operational amplifier triggered by said level of said potentiometer is applied to a coil of a relay and the current flow in said coil actuates a relay contact of said relay.

3. The automatic sizing device for measuring apparatus according to claim 1 in which each of said first and each of said second trigger circuits includes means for setting an individual trigger level whereby a control signal is generated only when. (1) said first amplifier means output exceeds in value the individual trigger level of a first trigger circuit or (2) said second amplifier means output exceeds in value the individual trig ger level of a second trigger circuit.

4. The automatic sizing device for measuring apparatus according to claim 1 in which each said first trigger circuit includes means for setting a first trigger level, means for providing a working condition control signal when each first trigger level is exceeded by the output level of said first amplifier means,

each said second trigger circuit includes means for setting a second trigger level, means for providing an on size working condition control signal when each second trigger level is exceeded by the output level of said second amplifier means. 

1. An automatic sizing device for measuring apparatus comprising, means for detecting a variation of a dimension of a work, converting means for converting said variation into an electric quantity, an output of said converting means being applied via a synchronous rectifier to first amplifier means, an output of said first amplifier means being indicated on an indicator as a variation of a whole range of process of a grinding, an output of said first amplifier means being applied to a single or multiple first trigger circuits, outputs of said first trigger circuits generating a single or multiple control signals for controlling a working condition of said work, said output of said first amplifier means being applied via second amplifier means to a single or multiple second trigger circuits, outputs of said second triggers circuit generating a single or multiple control signals for controlling a working condition near and/or on size.
 2. The automatic sizing device for measuring apparatus according to claim 1, wherein said first and second triggEr circuits each include, respectively, an operational amplifier with a positive feed back and a potentiometer for setting a trigger level of said operational amplifier, an output of said operational amplifier triggered by said level of said potentiometer is applied to a coil of a relay and the current flow in said coil actuates a relay contact of said relay.
 3. The automatic sizing device for measuring apparatus according to claim 1 in which each of said first and each of said second trigger circuits includes means for setting an individual trigger level whereby a control signal is generated only when (1) said first amplifier means output exceeds in value the individual trigger level of a first trigger circuit or (2) said second amplifier means output exceeds in value the individual trigger level of a second trigger circuit.
 4. The automatic sizing device for measuring apparatus according to claim 1 in which each said first trigger circuit includes means for setting a first trigger level, means for providing a working condition control signal when each first trigger level is exceeded by the output level of said first amplifier means, each said second trigger circuit includes means for setting a second trigger level, means for providing an on size working condition control signal when each second trigger level is exceeded by the output level of said second amplifier means. 